Erector spinae plane block level does not impact analgesic efficacy in enhanced recovery for lumbar spine surgery

BACKGROUND CONTEXT

Postoperative pain control following spine surgery can be difficult. The Enhanced Recovery After Surgery (ERAS) programs use multimodal approaches to manage postoperative pain. While an erector spinae plane block (ESPB) is commonly utilized, the ideal distance for injection from the incision, referred to as the ES (ESPB to mid-surgical level) distance, remains undetermined.

PURPOSE

We evaluated the impact of varying ES distances for ESPB on Numerical Rating Scale (NRS) measures of postoperative pain within the ERAS protocol.

STUDY DESIGN/SETTING

Retrospective observational study.

PATIENT SAMPLE

Adult patients who underwent elective lumbar spine fusion surgery.

OUTCOME MEASURES

Primary outcome measures include the comparative postoperative NRS scores across groups at immediate (T1), 24 (T2), 48 (T3), and 72 (T4) hours postsurgery. For secondary outcomes, a propensity matching analysis compared these outcomes between the ERAS and non-ERAS groups, with opioid-related recovery metrics also assessed.

METHODS

All included patients were assigned to one of three ERAS groups according to the ES distance: Group 1 (G1, ES > 3 segments), Group 2 (G2, ES = 2-3 segments), and Group 3 (G3, ES<2 segments). Each patient underwent a bilateral ultrasound-guided ESPB with 60 mL of diluted ropivacaine or bupivacaine.

RESULTS

Patients within the ERAS cohort reported mild pain (NRS < 3), with no significant NRS variation across G1 to G3 at any time. Sixty-five patients were matched across ERAS and non-ERAS groups. The ERAS group exhibited significantly lower NRS scores from T1 to T3 than the non-ERAS group. Total morphine consumption during hospitalization was 26.7 mg for ERAS and 41.5 mg for non-ERAS patients. The ERAS group resumed water and food intake sooner and had less postoperative nausea and vomiting.

CONCLUSIONS

ESPBs can be effectively administered at or near the mid-surgical level to the low thoracic region for lumbar spine surgeries. Given challenges with sonovisualization, a lumbar ESPB may be preferred to minimize the risk of inadvertent pleural injury.

MRI-based lesion quality score assessing ossification of the posterior longitudinal ligament of the cervical spine

BACKGROUND CONTEXT

No method currently exists for MRI-based determination of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine using objective criteria.

PURPOSE

The purpose of this study was to develop an MRI-based score to determine whether a lesion represents a cervical OPLL lesion and to establish the objective diagnostic value.

STUDY DESIGN

Retrospective cohort in a single medical institution.

PATIENT SAMPLE

Thirty-five patients undergoing surgery for OPLL (Group A) and 99 patients undergoing cervical disc arthroplasty for soft disc herniation (Group B) between 2011 and 2020 were retrospectively included. All OPLL lesions on unenhanced MRI scan were correlated with a corresponding CT scan. Demographics were comparable between the two groups.

OUTCOME MEASURES (PHYSIOLOGIC MEASURES)

Using unenhanced magnetic resonance imaging (MRI), the T1- and T2- lesion quality (LQ) scores were calculated. Receiver operating characteristic (ROC) analysis was performed to calculate the area-under-the-curve (AUC) of both LQ scores as a predictor of the presence of OPLL. Computed tomography (CT)-based Hounsfield unit (HU) values of OPLL lesions were obtained and compared with both LQ scores. The LQ scores for MRI scanners from different manufacturers were compared using Student's t test to confirm the validity of the LQ score by scanner type.

METHODS

The regions of interest for signal intensity (SI) were defined as the darkest site of the lesion and the cerebrospinal fluid (CSF) at the cerebellomedullary cistern. The T1 and T2 LQ scores were measured as the ratio of the SI at the darkest site of the lesion divided by the SI of the CSF.

RESULTS

The T1 and T2 LQ scores in Group A were significantly lower than those in Group B (p<.001). ROC analysis determined that T1 and T2 LQ scores of 0.46 and 0.07, respectively, could distinguish the presence of OPLL with an accuracy of 0.93 and 0.89, respectively (p<.001). When the T1 LQ score of the lesion is <0.46, a diagnosis of OPLL may be suspected with 100% sensitivity and 92.3% specificity. The HU of the lesion had a moderate negative correlation with the T1 LQ score (r=-0.665, p<.0001). Both LQ scores were unaffected by manufacturer type.

CONCLUSIONS

This study found a correlation between the MRI-based T1 LQ scores and CT-based HU value for identifying OPLL lesions. Additional studies will be needed to validate that the T1 LQ score from the unenhanced MRI scan can identify cervical OPLL.

Proliferation and Differentiation Potential of Bone Marrow-Derived Mesenchymal Stem Cells From Children With Polydactyly and Adults With Basal Joint Arthritis

This study compared the proliferation and differentiation potential of bone marrow-derived mesenchymal stem cells (BMSCs) derived from infants with polydactyly and adults with basal joint arthritis. The proliferation rate of adult and infant BMSCs was determined by the cell number changes and doubling times. The γH2AX immunofluorescence staining, age-related gene expression, senescence-associated β-galactosidase (SA-β-gal) staining were analyzed to determine the senescence state of adult and infant BMSCs. The expression levels of superoxide dismutases (SODs) and genes associated with various types of differentiation were measured using Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR). Differentiation levels were evaluated through histochemical and immunohistochemical staining. The results showed that infant BMSCs had a significantly higher increase in cell numbers and faster doubling times compared with adult BMSCs. Infant BMSCs at late stages exhibited reduced γH2AX expression and SA-β-gal staining, indicating lower levels of senescence. The expression levels of senescence-related genes (p16, p21, and p53) in infant BMSCs were also lower than in adult BMSCs. In addition, infant BMSCs demonstrated higher antioxidative ability with elevated expression of SOD1, SOD2, and SOD3 compared with adult BMSCs. In terms of differentiation potential, infant BMSCs outperformed adult BMSCs in chondrogenesis, as indicated by higher expression levels of chondrogenic genes (SOX9, COL2, and COL10) and positive immunohistochemical staining. Moreover, differentiated cells derived from infant BMSCs exhibited significantly higher expression levels of osteogenic, tenogenic, hepatogenic, and neurogenic genes compared with those derived from adult BMSCs. Histochemical and immunofluorescence staining confirmed these findings. However, adult BMSCs showed lower adipogenic differentiation potential compared with infant BMSCs. Overall, infant BMSCs demonstrated superior characteristics, including higher proliferation rates, enhanced antioxidative activity, and greater differentiation potential into various lineages. They also exhibited reduced cellular senescence. These findings, within the context of cellular differentiation, suggest potential implications for the use of allogeneic BMSC transplantation, emphasizing the need for further in vivo investigation.

Multilineage differentiation potential in the infant adipose- and umbilical cord-derived mesenchymal stem cells

BACKGROUND

This study aims to compare the biological properties of infant adipose-derived mesenchymal stem cells (infant ADSCs) from excised polydactyly fat tissue and umbilical cord-derived mesenchymal stem cells (UCSCs) in terms of proliferation and differentiation capabilities. The proliferation of infant ADSCs and UCSCs was analyzed by determining the fold changes of cell numbers and doubling time periods.

METHODS

The state of senescence and replicative stress was compared by analyzing the expression of age-related genes, senescence-associated β-galactosidase (SA-β-gal) staining, and phosphorylated histone variant H2AX (γH2AX) immunofluorescence staining. The expression levels of superoxide dismutase ( SODs ) and genes related to multilineage differentiation were analyzed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Differentiation levels were determined using histochemical staining, immunohistochemical staining, and immunofluorescence staining.

RESULTS

Infant ADSCs exhibited higher proliferation rates and expression levels of SOD1 , SOD2 , and SOD3 at passages 3-5 compared with UCSCs. Senescence related genes ( p16 , p21 , and p53 ), SA-β-gal staining, and replicative stress analysis were reduced in infant ADSCs. The expression levels of chondrogenic genes ( COL2 and COL10 ), osteogenic genes ( RUNX2 and ALP ), adipogenic genes ( LPL ), and hepatogenic genes ( ALB and TAT ) in infant ADSC-differentiated cells were significantly higher than those in UCSCs. Histochemical and immunofluorescence staining confirmed these results. Only the expression levels of tenogenic genes ( MMP3 , DCN , and COL3 ) in infant ADSC-differentiated cells were lower than those in UCSCs.

CONCLUSION

Infant ADSCs exhibit higher proliferation rates, reduced cellular senescence and replicative stress, better antioxidative activity, and higher differentiation potential toward chondrogenic, osteogenic, adipogenic and hepatogenic lineages than UCSCs.

Reducing surgical site infections after spine surgery: the optimal amount of normal saline for intra-wound irrigation

BACKGROUND CONTEXT

Surgical site infection (SSI) following lumbar surgery can increase healthcare costs and lead to poor clinical outcome. Irrigation of wounds with saline solution is widely accepted globally and safe for nearly all kinds of surgery. However, the efficacy of different volumes of wound irrigation has not been addressed in elective spine surgery. The role and the optimal amount of intraoperative wound saline irrigation in preventing SSI in clean spinal surgery remain unclear.

PURPOSE

We aimed to investigate if insufficient intraoperative irrigation may be a risk factor for postoperative SSI. Additionally, we investigated the optimal amount of normal saline (NS) for irrigation to prevent postoperative SSI.

STUDY DESIGN

This is a retrospective study of patients with degenerative spinal stenosis who were treated surgically. Patients were grouped according to the amount of intra-wound irrigation during surgery.

PATIENT SAMPLE

We included 444 patients with degenerative lumbar spinal conditions who had undergone one to five level open spinal fusion surgeries from January 2015 through April 2020.

OUTCOME MEASURES

The definition of superficial or deep SSI in this study was based on the Centers for Disease Control and Prevention criteria for SSI. The fusion status accessed was based on the Bridwell grading system at the final follow-up. Self-reported and clinical outcome measures include visual analog scale and Oswestry Disability Index.

METHODS

A total of 193 patients underwent irrigation with a bulb syringe with manual method (B group) with 2,000 mL NS; 251 patients underwent interpulse battery-powered device irrigation (P group) with >6,000 mL NS. Based on our protocolized departmental guidelines, all patients received the same preoperative preparation and standard surgical steps and postoperative care plan. Patients' demographic and surgical parameters were recorded. The main outcome measures included superficial wound infection, deep infection and overall infection.

RESULTS

The incidence of overall SSI was 4.66% in the B group and 1.59% in the P group. The univariate analysis revealed a significant correlation with DM and irrigation amount per hour during surgery but not age, BMI, smoking, operative duration, fusion level, or blood loss. We determined the optimal irrigation amount during surgery as 1,400 mL per hour based on the receiver operating characteristic (ROC) curve (sensitivity, 92.3%; specificity, 44.1%). This was statistically significant (p=.033) with an odds ratio of 9.284 (95% confidence interval 1.2-72.0). In the analysis of surgical factors, the infection group had a significantly lower irrigation amount during surgery. To summarize, patients with diabetes and those receiving less than 1,400 mL of NS/hour had a higher likelihood of developing SSI.

CONCLUSIONS

We observed that diabetes and lower volume of intraoperative irrigation were both risk factors for postoperative SSI following degenerative lumbar spine surgery. To reduce SSI in lumbar spine surgery, intra-wound irrigation with more than 1,400 mL/h of NS was recommended.

Preoperative planning of compact zone trajectory is necessary in treating osteoporotic vertebral compression fracture with endplate involvement: A prospective randomized controlled study

BACKGROUND

This prospective randomized controlled study compares the clinical and radiological outcomes between reduction methods with or without compact trabecular bone during percutaneous kyphoplasty in osteoporotic vertebral fractures.

METHODS

The cohort of 100 patients who underwent percutaneous kyphoplasty was randomly divided into group A (guide pin and balloon introduced directly into fracture site) and group B (guide pin and balloon inserted away fracture site). The surgery duration, clinical and radiological outcomes postoperatively and at follow-up, and complications of cement leakage and adjacent fracture were recorded. Patients were followed up for an average of 20.18 months. The clinical outcomes were assessed using the Oswestry Disability Index and visual analog scale.

RESULTS

The two groups had similar patient demographics, surgery times, and volume of cement injected. The method using elevation of the collapsed endplate indirectly had no significant influence on radiological outcomes but significantly decreased the occurrence of intradiscal cement leakage and improved 1- and 12-month postoperative functional outcomes.

CONCLUSION

Elevating and reinforcing the collapsed endplate rather than just filling the defect during percutaneous kyphoplasty is safe and effective. This technique decreased pain and improved function with lower rates of further collapse of the osteoporotic vertebrae compared to defect-filling alone.

Differences in productivity and collaboration patterns on spine-related research between neurosurgeons and orthopedic spine surgeons: Bibliometric analysis

BACKGROUND

Spinal surgeries are commonly performed by neurosurgeons and orthopedic spine surgeons, with many spine-related articles published by them. However, there has been limited research that directly compares their research achievements. This article conducted a comparative analysis of spine-related research achievements between neurosurgeons and orthopedic spine surgeons. This study examines differences in productivity and impact on spine-related research between them using these measures, particularly with a novel clustering algorithm.

METHODS

We gathered 2148 articles written by neurosurgeons and orthopedic spine surgeons from the Web of Science core collections, covering the period from 2013 to 2022. To analyze author collaborations, we employed the follower-leader clustering algorithm (FLCA) and conducted cluster analysis. A 3-part analysis was carried out: cluster analysis of author collaborations; mean citation analysis; and a category, journal, authorship, L-index (CJAL) score based on article category, journal impact factors, authorships, and L-indices. We then utilized R to create visual displays of our findings, including circle bar charts, heatmaps with dendrograms, 4-quadrant radar plots, and forest plots. The mean citations and CJAL scores were compared between neurosurgeons and orthopedic spine surgeons.

RESULTS

When considering first and corresponding authors, orthopedics authors wrote a greater proportion of the articles in the article collections, accounting for 75% (1600 out of 2148). The CJAL score based on the top 10 units each also favored orthopedic spine surgeons, with 71% (3626 out of 6139) of the total score attributed to them. Using the FLCA, we observed that orthopedic spine surgeons tended to have more collaborations across countries. Additionally, while citation per article favored orthopedic spine surgeons with standard mean difference (= -0.66) and 95%CI: -0.76, -0.56, the mean CJAL score in difference (= 0.34) favored neurosurgeons with 95%CI: 0.24 0.44.

CONCLUSION

Orthopedic spine surgeons have a higher number of publications, citations, and CJAL scores in spine research than those in neurosurgeons. Orthopedic spine surgeons tend to have more collaborations and coauthored papers in the field. The study highlights the differences in research productivity and collaboration patterns between the 2 authors in spine research and sheds light on potential contributing factors. The study recommends the use of FLCA for future bibliographical studies.

The Impact of Cage and End plate-Related Factors on Cage Subsidence in Oblique Lateral Interbody Fusion

OBJECTIVES

To identify cage and end plate factors of cage subsidence (CS) in patients who underwent oblique lateral interbody fusion (OLIF) and their association with patient-reported outcomes.

METHODS

Sixty-one patients (43 women and 18 men), with a total of 69 segments (138 end plates) which underwent OLIF at a single academic institution between November 2018 and November 2020, were included. All the end plates were separated into CS and nonsubsidence groups. Cage-related parameters (cage height, cage width, cage insertion level, and cage position) and end plate-related parameters (position of end plate, Hounsfield unit value of the vertebra, end plate concave angle [ECA], end plate injury, and angular mismatch measured with cage/end plate angle [C/EA]) were compared and analyzed using logistic regression to predict CS. Receiver operating characteristic curve analysis was used to determine the cutoff points of the parameters.

RESULTS

Postoperative CS was identified in 50 of the 138 end plates (36.2%). The CS group had significantly lower mean Hounsfield unit values of the vertebra, higher rate of end plate injury, lower ECA, and higher C/EA than the nonsubsidence group. ECA and C/EA were identified as independent risk factors for developing CS. The optimal cutoff points for ECA and C/EA were 176.9° and 5.4°, respectively.

CONCLUSIONS

An ECA greater than 176.9° and a cage/end plate angular mismatch greater than 5.4° were found to be independent risk factors of postoperative CS after the OLIF procedure. These findings aid in preoperative decision-making and intraoperative technical guidance.

Biomechanical Effects of a Novel Pedicle Screw W-Type Rod Fixation for Lumbar Spondylolysis: A Finite Element Analysis

Lumbar spondylolysis involves anatomical defects of the pars interarticularis, which causes instability during motion. The instability can be addressed through instrumentation with posterolateral fusion (PLF). We developed a novel pedicle screw W-type rod fixation system and evaluated its biomechanical effects in comparison with PLF and Dynesys stabilization for lumbar spondylolysis via finite element (FE) analysis. A validated lumbar spine model was built using ANSYS 14.5 software. Five FE models were established simulating the intact L1-L5 lumbar spine (INT), bilateral pars defect (Bipars), bilateral pars defect with PLF (Bipars_PLF), Dynesys stabilization (Bipars_Dyn), and W-type rod fixation (Bipars_Wtyp). The range of motion (ROM) of the affected segment, the disc stress (DS), and the facet contact force (FCF) of the cranial segment were compared. In the Bipars model, ROM increased in extension and rotation. Compared with the INT model, Bipars_PLF and Bipars_Dyn exhibited remarkably lower ROMs for the affected segment and imposed greater DS and FCF in the cranial segment. Bipars_Wtyp preserved more ROM and generated lower stress at the cranial segment than Bipars_PLF or Bipars_Dyn. The injury model indicates that this novel pedicle screw W-type rod for spondylolysis fixation could return ROM, DS, and FCF to levels similar to preinjury.

Posterior instrumentation for osteoporotic fractures in the thoracic or lumbar spine: Cement-augmented pedicle screws vs hybrid constructs

BACKGROUND

Cement-augmented pedicle screws (CPS) and hybrid construct (HC), consisting of pedicle screws and additional hooks, are common fixation methods for osteoporotic spine fracture. No study has compared surgical results of CPS and HC for treating osteoporotic spine fracture. The aim of the study was to compare surgical results using CPS or HC for osteoporotic fractures of the thoracic or lumbar spine.

METHODS

This retrospective cohort study included 84 patients who received surgical treatment with CPS (n = 43) or HC (n = 41) for osteoporotic spine fractures from January 2011 to December 2015, with a mean follow-up of 67 months. Sixty-five patients with neurological deficits received long posterior instrumentation, short posterior decompression, and posterolateral fusion. The 19 patients without neurologic deficits received long posterior instrumentation without posterior decompression and fusion. Radiographic, clinical, and neurologic outcomes were evaluated.

RESULTS

The HC group had significantly shorter operative times (231 vs 258 minutes), greater blood loss (497 vs 427 mL), better immediate postoperative kyphosis reduction (10.6° vs 9.1°), and greater final reduction loss (9.8° vs 7.1°) than the CPS group. In both groups, significant loss of the kyphotic angle was apparent during follow-up. Improved ambulation after surgery occurred in 51.2% and 58.5% of patients in the CPS and HC groups, respectively. Neurologic function after surgery improved 0.5 and 0.7 grades in the CPS and HC groups, respectively. Implants failed in 2.3% and 2.4% of patients in the CPS and HC groups, respectively. The incidence of cement leakage from screw augmentation was 38.9%.

CONCLUSION

The CPS and HC techniques for treating osteoporotic fractures of the thoracic or lumbar spine did not differ statistically in terms of improved radiologic and clinical outcomes, final neurologic and ambulatory function, or implant failure rates, making them equally comparable alternatives.

Outcome of Ti/PEEK Versus PEEK Cages in Minimally Invasive Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

Retrospective case-control study.

OBJECTIVES

This study aims to present the clinical and radiographical outcomes of the titanium-polyetheretherketone (Ti/PEEK) composite cage compared to those of the standard PEEK cage in patients receiving minimally invasive transforaminal lumbar interbody fusion (MI-TLIF).

METHODS

Patients receiving 1 level MI-TLIF between October 2015 and October 2017 were included with a minimum of 2-year follow-up. The patients were segregated into 2 groups; Ti/PEEK group and PEEK group. Each patient was propensity-matched using preoperative age, sex, and body mass index. Early fusion rate was evaluated by computed tomography at postoperative 6 months. Clinical outcomes were assessed using the visual analog scale (VAS) and Oswestry Disability Index (ODI) scores.

RESULTS

After matching, there were 27 patients included in each group. The demographics, diagnosis, and surgical details were not significantly different between the 2 groups. The 6-month rate was 88.9% in Ti/PEEK group. The fusion rate and cage subsidence rate had no difference between the 2 groups. The complication rate in the Ti/PEEK group was comparable to that in the PEEK group. There was no difference in VAS and ODI scores during a 2-year follow-up period.

CONCLUSIONS

The use of Ti/PEEK composite cage was as safe and effective as the use of PEEK cage in MI-TLIF. The 6-month fusion rate was 88.9%. Our finding revealed comparable clinical results for surgeons using Ti/PEEK composite cages in MI-TLIF compared to those using the PEEK cage.

Shorter screw lengths in dynamic Dynesys fixation have less screw loosening: From clinical investigation to finite-element analysis

BACKGROUND

The dynamic Dynesys Stabilization System preserves lumbar mobility at instrumented levels. This study investigated the effect of screw length on screw loosening (SL) after dynamic Dynesys fixation and screw displacement during lumbar motion, using clinical investigation and finite-element (FE) analysis.

METHODS

Clinical data of 50 patients with degenerative spondylolisthesis treated with decompression and Dynesys fixation in 2011 were analyzed retrospectively. Horizontal sliding displacement and vertical displacement of screw tips at L4 were analyzed postoperatively using displacement-controlled FE analysis at the L4-L5 level with screw lengths 45 (long screw), 36 (median screw), and 27 (short screw), and 6.4 mm in diameter, under flexion, extension, lateral bending, and rotation.

RESULTS

In 13 patients (13/50, 26%), 40 screws (40/266, 15%) were loose at mean follow-up of 101.3 ± 4.4 months. Radiographic SL at 35, 40, 45, and 50 mm were 7.7%, 10.7%, 12.1%, and 37.5%, respectively, regardless of the fixation level ( p = 0.009). FE analysis revealed that the long screw model with corresponding longer lever arm had maximal horizontal sliding displacement under all directions and maximal vertical displacement, except for lateral bending.

CONCLUSION

Shorter screws in Dynesys fixation may help avoid dynamic SL. Clinically, 50 mm screws showed the greatest SL and median screw screws demonstrated the least displacement biomechanically.

Investigation of preoperative asymptomatic bacteriuria as a risk factor for postvertebroplasty infection

BACKGROUND

Postvertebroplasty infection (PVI) is a catastrophic complication after vertebroplasty (VP). Although the urinary tract has been considered as a source of infectious pathogens, whether asymptomatic bacteriuria (ASB) is a risk factors for PVI remains unknown.

METHODS

This retrospective study included 716 patients (207 males; 509 females) treated with VP for osteoporotic vertebral fractures in a single medical center between May 2015 and December 2019. Clinical symptoms, urinalysis results, and culture data were collected preoperatively to identify patients with ASB. The primary outcome was PVI at the index level during follow-up. Demographic data and laboratory test results were compared between the PVI and non-PVI groups.

RESULTS

The mean age of the cohort was 78.6 ± 9.6 (range, 63-106). The prevalence of ASB was 14.1%, with female predominance (63.4%). The overall PVI rate was 1.26% (9/716). The PVI group had more patients with ASB (4/9, 44.4%) than did the non-PVI group (97/707, 13.7%) (p = 0.027). The rate of ASB treatment was similar between the PVI and non-PVI groups (25% vs. 23.7%, respectively). No case of PVI was caused by the urine culture pathogen. Multivariate analysis identified the following risk factors for PVI: ASB (odds ratio [OR], 5.61; 95% CI, 1.14-27.66; p = 0.034), smoking (OR, 16.26; 95% CI, 2.58-102.65; p = 0.003), and malignancy (OR 7.27; 95% CI, 1.31-40.31; p = 0.023).

CONCLUSION

ASB was not uncommon among patients admitted for VP and should be considered a marker of relatively poor host immunity. Preoperative ASB, a history of malignancy, and smoking were identified as significant risk factors for PVI.

CT Hounsfield unit is a reliable parameter for screws loosening or cages subsidence in minimally invasive transforaminal lumbar interbody fusion

Retrospective cohort study. To validate computed tomography (CT) radiodensity in Hounsfield units (HU) as a prognostic marker for pedicle screw loosening or cage subsidence in minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). The retrospective study involved 198 patients treated with MI-TLIF. Screw loosening (SL), cage subsidence (CS), and fusion status were assessed by plain radiographs. The risk factors of SL and CS were identified using logistic regression. A total of 258 levels and 930 screws were analyzed. During a 2-year follow-up, 16.2% and 24.7% of patients had CS and SL respectively. The cut-off value of L1 HU for predicting SL or CS was 117. The L1 HU < 117 and BMI ≥ 25 were two independent risk factors. The risk of SL or CS was 4.1 fold in patients L1 HU < 117 and 2.6 fold in patients with BMI ≥ 25. For patients concurrently having BMI ≥ 25 and pre-op L1 HU < 117, the risk was 4.3 fold. Fusion rate and clinical outcome were comparable in patients with SL or CS. L1 HU < 117 and BMI > 25 were two independent risk factors that can be screened preoperatively for preventing SL or CS and lead to better management of patients undergoing MI-TLIF.

Superior facet joint violation between open and minimally invasive techniques in lumbar fusion surgery: An updated systematic review and meta-analysis

BACKGROUND

Superior facet joint violation (FJV) is a potential risk factor for adjacent segment disease following lumbar fusion surgery. We sought to conduct a systematic review and meta-analysis to compare screw-related superior FJV rates between the open and different minimally invasive (MI) techniques-fluoroscopy-based, 3D-image navigation, and navigation with robotic assistance-in adult lumbar fusion surgery.

METHODS

We searched original articles comparing the rates of screw-related FJV between the open and different MI techniques in adult lumbar fusion surgery for lumbar degenerative diseases in PubMed, EMBASE, and the Cochrane Library from inception to September 2021. We compared the numbers of top-level pedicle screws and associated superior FJVs in the main analyses and performed subgroup analysis based on different MI techniques to examine whether individual MI approaches differed in superior FJV rate. Risk ratio (RR) and 95% confidence interval (CI) were calculated in a random-effect meta-analysis.

RESULTS

Included in the meta-analysis were 16 articles with 2655 patients and 4638 top-level pedicle screws. The pooled analysis showed no significant difference in superior FJV rates between the MI and open groups (RR: 0.89, 95% CI: 0.62-1.28). The subgroup analysis demonstrated that the overall rates of superior FJV were 27.1% (411/1518) for fluoroscopy-based, 7.1% (43/603) for 3D-image navigation, and 3.2% (7/216) for navigation with robotic assistance. Compared with the open method, the overall RRs were 1.53 (95% CI: 1.19-1.96) for fluoroscopy-based, 0.41 (95% CI: 0.22-0.75) for 3D-image navigation, and 0.25 (95% CI: 0.08-0.72) for navigation with robotic assistance.

CONCLUSION

Among the three common MI techniques, fluoroscopy-based can be associated with a higher risk of superior FJV, while both 3D-image navigation and navigation with robotic assistance may be associated with lower risks as compared with the open method. Considering the limitations of the study, more trials are needed to prove these clinical findings.

Thematic analysis of articles on artificial intelligence with spine trauma, vertebral metastasis, and osteoporosis using chord diagrams: A systematic review and meta-analysis

BACKGROUND

Spine trauma, vertebral metastases, and osteoporosis (SVO) can result in serious health problems. If the diagnosis of SVO is delayed, the prognosis may be deteriorated. The use of artificial intelligence (AI) is an essential method for minimizing the diagnostic errors associated with SVO. research achievements (RAs) of SVO on AI are required as a result of the greatest number of studies on AI solutions reported. The study aimed to: classify article themes using visualizations, illustrate the characteristics of SVO on AI recently, compare RAs of SVO on AI between entities (e.g., countries, institutes, departments, and authors), and determine whether the mean citations of keywords can be used to predict article citations.

METHODS

A total of 31 articles from SVO on AI (denoted by T31SVOAI) have been found in Web of Science since 2018. The dominant entities were analyzed using the CJAL score and the Y-index. Five visualizations were applied to report: the themes of T31SVOAI and their RAs in comparison for article entities and verification of the hypothesis that the mean citations of keywords can predict article citations, including: network diagrams, chord diagrams, dot plots, a Kano diagram, and radar plots.

RESULTS

There were five themes classified (osteoporosis, personalized medicine, fracture, deformity, and cervical spine) by a chord diagram. The dominant entities with the highest CJAL scores were the United States (22.05), the University of Pennsylvania (5.72), Radiology (6.12), and Nithin Kolanu (Australia) (9.88). The majority of articles were published in Bone, J. Bone Miner. Res., and Arch. Osteoporos., with an equal count (=3). There was a significant correlation between the number of article citations and the number of weighted keywords (F = 392.05; P < .0001).

CONCLUSION

A breakthrough was achieved by displaying the characteristics of T31SVOAI using the CJAL score, the Y-index, and the chord diagram. Weighted keywords can be used to predict article citations. The five visualizations employed in this study may be used in future bibliographical studies.

Whole-Exome Sequencing Identifies Genetic Variants for Severe Adolescent Idiopathic Scoliosis in a Taiwanese Population

Adolescent idiopathic scoliosis (AIS) is a three-dimensional spinal curvature deformity that appears in the adolescent period. In this study, we performed whole-exome sequencing on 11 unrelated Taiwanese patients with a Cobb's angle greater than 40 degrees. Our results identified more than 200 potential pathogenic rare variants, however, most of which were carried only by one individual. By in silico pathogenicity annotation studies, we found that TTN, CLCN1, and SOX8 were the most important genes, as multiple pathogenic variants were within these genes. Furthermore, biological functional annotation indicated critical roles of these AIS candidate genes in the skeletal muscle. Importantly, a pathogenic variant on SOX8 was shared by over 35% of the patients. These results highlighted TTN, CLCN1, and SOX8 as the most likely susceptibility genes for severe AIS.

Comparing the similarity and differences in MeSH terms associated with spine-specific journals using the forest plot: A bibliometric analysis

BACKGROUND

A common concern in the literature is the comparison of the similarities and differences between research journals, as well as the types of research they publish. At present, there are no clear methodologies that can be applied to a given article of interest. When authors use an effective and efficient method to locate journals in similar fields, they benefit greatly. By using the forest plot and major medical subject headings (MeSH terms) of Spine (Phila Pa 1976) compared to Spine J, this study: displays relatively similar journals to the target journal online and identifies the effect of the similarity odds ratio of Spine (Phila Pa 1976) compared to Spine J.

METHODS

From the PubMed library, we downloaded 1000 of the most recent top 20 most similar articles related to Spine (Phila Pa 1976) and then plotted the clusters of related journals using social network analysis (SNA). The forest plot was used to compare the differences in MeSH terms for 2 journals (Spine (Phila Pa 1976) and Spine J) based on odds ratios. The heterogeneity of the data was evaluated using the Q statistic and the I-square (I2) index.

RESULTS

This study shows that: the journals related to Spine (Phila Pa 1976) can easily be presented on a dashboard via Google Maps; 8 journal clusters were identified using SNA; the 3 most frequently searched MeSH terms are surgery, diagnostic imaging, and methods; and the odds ratios of MeSH terms only show significant differences with the keyword "surgery" between Spine (Phila Pa 1976) and Spine J with homogeneity at I2 = 17.7% (P = .27).

CONCLUSIONS

The SNA and forest plot provide a detailed overview of the inter-journal relationships and the target journal using MeSH terms. Based on the findings of this research, readers are provided with knowledge and concept diagrams that can be used in future submissions to related journals.

Citation analysis of the 100 top-cited articles on discectomy via endoscopy since 2011 using alluvial diagrams: bibliometric analysis

Background

Percutaneous endoscopic lumbar discectomy (PELD) is synonymous with percutaneous endoscopic transforaminal discectomy (PETD) and percutaneous endoscopic interlaminar discectomy (PEID). PEID has gained increasing recognition for its small incision, quick recovery, short hospital stay, and equivalent clinical outcome to open surgery. Numerous articles related to PEID have been published in the literature. However, which countries, journals, subject categories, and articles have ultimate influence remains unknown. The study aimed to (1) display influential entities in 100 top-cited PEID-related articles (T100PEID) on the alluvial diagram and (2) investigate whether medical subject headings (i.e., MeSH terms) can be used to predict article citations.

Methods

T100PEID data can be found since 2011 in the PubMed and Web of Science (WOS) databases. Using alluvial diagrams, citation analysis was conducted to compare the dominant entities. We used social network analysis (SNA) to classify MeSH terms and research areas extracted from PubMed and WOS. The difference in article citations across subject categories and the predictive power of MeSH terms on article citations in T100 PEID were examined using one-way analysis of variance (ANOVA) and regression analysis.

Results

A total of 81% of T100PEID is occupied by the top three countries (the US, China, and South Korea). There was an overall T100PEID impact factor of 41.3 (IF = citations/100). Articles were published in Spine (Phila Pa 1976) (23%; IF = 41.3). Six subject categories were classified using the SNA. The most cited article authored by D Scott Kreiner from Ahwatukee Sports and Spine in the US state of Phoenix had 123 citations in PubMed. The network characteristics of T100PEID are displayed on the alluvial diagram. No difference was found in article citations among subject categories (F = 0.813, p = 0.543). The most frequently occurring MeSH term was surgery. MeSH terms were evident in the prediction power of the number of article citations (F = 15.21; p < 0 .001).

Conclusion

We achieved a breakthrough by displaying the T100PEID network characteristics on the alluvial plateau. The MeSH terms can be used to classify article subject categories and predict T100PEID citations. The alluvial diagram can be applied to bibliometrics on 100 top-cited articles in future studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40001-022-00782-0.

An Alluvial diagram was drawn to display the network characteristics of T100PEID, which is novel and modern in the literature.

The method of drawing the Alluvial demonstrated in detail with documents in supplemental digital contents can be applied to make bibliometric studies brief, concise, and powerful.

The impact beam plot (IBP) is an additional visualization introduced in this study. The online IBP was demonstrated and worthy of future similar studies to highlight the most influential articles with a glance at a picture.

Efficacy of Povidone Iodine Solution in the Prevention of Surgical Site Infections in Minimally Invasive Instrumented Spinal Fusion Surgery

STUDY DESIGN

A retrospective case-controlled study.

OBJECTIVES

To evaluate overall infection rate and adverse event after harvesting bone graft soaking and surgical wound irrigation by povidone iodine solution (PVI) in the minimally invasive instrumented spinal fusion surgery. In order to reduce the rate of surgical site infection in spinal surgery, surgical wound irrigation by povidone iodine solution has been well-established. However, the efficacy of autologous bone graft soaking by PVI has not been evaluated before.

METHODS

This is a retrospective cohort study. 120 patients were enrolled in the PVI group and compared with 124 patients in the historical cohort. In the PVI group, the harvesting autologous bone graft was soaking and the surgical wound was also irrigated by diluted PVI solution. The outcome measures were overall infection rate, superficial wound infection and deep infection. In addition, the delayed union of the fusion mass was also evaluated through the radiograph evaluation.

RESULTS

Both groups shared similar patient demographics instead of body mass index. The use of PVI solution had decreased the overall infection rate (0% versus 4.03%, p = 0.026) and deep infection rate (0% versus 3.23%, p = 0.047). In addition, there was no delayed bone healing in the PVI group after autologous bone graft soaking.

CONCLUSIONS

In this study, we conclude that harvested autologous bone graft after PVI soaking in spinal fusion surgery can decrease the incidence of deep infection.

Classification and citation analysis of the 100 top-cited articles on adult spinal deformity since 2011: A bibliometric analysis

BACKGROUND

Studies of the 100 most-cited articles are reported for many subjects. However, none has analyzed the article characteristics associated with high citation frequency. This study aims to (1) graphically depict characteristics of the 100 top-cited articles addressing adult spinal deformity (ASD), (2) diagram the association between articles according to subject and major topic medical subject headings (MeSHs), and (3) investigate whether major topic MeSH correlates with article citation frequency.

METHODS

The 100 top-cited ASD publications since 2011 were retrieved using a PubMed Central search on May 6, 2020. Using titles and abstracts, eight subject categories were identified: surgery, conservative treatment, normal values in spinopelvic alignment, review, cervical alignment, classification, compensatory mechanism, and spine-hip relationship. Sankey diagrams were used to organize the information. Network analysis was performed according to article subject and major topic MeSHs. Pearson's r was used to determine whether the weighted number of citations correlates with major topic MeSHs and the number of citations.

RESULTS

The average number of citations per article was 34.8 (range, 19-156). The most represented country was USA (n = 51). The most productive and highly cited journal was Spine (Phila Pa 1976) (n = 34; average, 38.2 citations per article). The most frequent subject categories and major topic MeSHs were "surgery" (n = 53) and "scoliosis" (weighted count, 9.8), while articles with the subject "compensatory" had the highest average number of citations (64.7). The most highly cited article, by Dr. F. Schwab in 2012, had 156 citations. Network analysis revealed the relationships between these articles according to major topic MeSHs. The weighted number of citations according to major topic MeSHs correlated significantly with article citation frequency (Pearson's r, 0.57; p < 0.001).

CONCLUSION

Multiple characteristics of the 100 top-cited ASD articles are presented in diagrams to guide evidence-based clinical decision-making in ASD.

Healing of Vertebral Compression Fractures in the Elderly after Percutaneous Vertebroplasty-An Analysis of New Bone Formation and Sagittal Alignment in a 3-Year Follow-Up

BACKGROUND

Vertebral compression fractures, resulting in significant pain and disability, commonly occur in elderly osteoporotic patients. However, the current literature lacks long-term follow-up information related to image parameters and bone formation following vertebroplasty.

PURPOSE

To evaluate new bone formation after vertebroplasty and the long-term effect of vertebroplasty.

METHODS

A total of 157 patients with new osteoporotic compression fractures who underwent vertebroplasty were retrospectively analyzed. The image parameters, including wedge angles, compression ratios, global alignment, and new bone formation, were recorded before and after vertebroplasty up to three years postoperatively.

RESULTS

The wedge angle improved and was maintained for 12 months. The compression ratios also improved but gradually deteriorated during the follow-up period. New bone formation was found in 40% of the patients at 36 months, and the multivariate analysis showed that this might have been related to the correction of the anterior compression ratio.

CONCLUSIONS

Vertebroplasty significantly restored the wedge angles and compression ratios up to one year postoperatively, and new bone formation was noted on plain radiographs, which increased over time. Last, the restoration of vertebral parameters may contribute to new bone formation.

Predictability of the preoperative lateral fulcrum radiograph of success in one-level vertebroplasty to treat painful osteoporotic vertebral fracture

BACKGROUND

Restoration of height or angle has been reported following vertebroplasty (VP). The purpose of the study was to investigate the predictive value of the preoperative lateral fulcrum radiograph (LFR) of success in one-level VP for painful osteoporotic vertebral fracture.

METHODS

From January 2017 to January 2018, 71 patients (mean age, 76 years) receiving VP were retrospectively analyzed. Painful vertebra was defined as pseudarthrosis or edematous change in magnetic resonance imaging (MRI) scan. Fulcrum flexibility (FF) and fulcrum restoration index (FRI) of the vertebral wedge angle (VWA), regional kyphotic angle (RKA), and anterior vertebral body height (AVBH) were investigated. Back pain was evaluated using a visual analogue scale.

RESULTS

The 30 males and 41 females were followed for an average of 21 months. The sensitivity of LFR and MRI to detect pseudarthrosis was 92% and 97%, respectively. Preoperative FF of VWA, RKA, and AVBH was 52.4%, 58.3%, and 60%, respectively, indicating similar potential restoration ability. Postoperative average FRI for VWA, RKA, and AVBH was 1.29 ± 2.98, 0.46 ± 1.16, and 1.04 ± 1.68, respectively. Final average FRI was 0.94 ± 2.96, -0.03 ± 2.25, and 0.6 ± 2.04, respectively. VWA and AVBH had better immediate restoration, and VWA had better final maintenance. All parameters progressive lost significant levels of restoration to similar degrees but without increase in back pain.

CONCLUSION

LFR can help with evaluation for pseudarthrosis and the restoration effect of VP. VP had better immediate restoration of VWA and AVBH and better final VWA maintenance.

Incidences and Risk factors of Screw-related Superior Facet Articular Surface Violation at L4 and L5 levels in Transforaminal Lumbar Interbody Fusion: Open Surgery Versus Minimally Invasive Techniques

STUDY DESIGN

A retrospective comparative study with radiographic measurements.

OBJECTIVE

The aim of this study was to investigate incidences and risk factors of screw-related superior facet articular surface violation (FASV) and optimal pedicle screw angles (PSAs) to avoid FASV at L4 and L5 levels in transforaminal lumbar interbody fusion (TLIF) with either open surgery (OS) or minimal invasive (MIS) techniques with 3D C-arm navigation.

SUMMARY OF BACKGROUND DATA

L4 to S1 are common levels in TLIF. Adjacent segment diseases (ASD) following TLIF is not uncommon. Screw-related FASV at the superior level is one of the potential risk factors for ASD.

METHODS

In the OS and MIS groups, 111 and 110 screws were included at L4 level, and 114 and 110 screws at L5 level, respectively. Postoperative computed tomography examined screw-related FASV at L3-4 and L4-5 facet levels. The entry point was the location where pedicle screws placed into the facet joints.

RESULTS

The OS technique and insertion at the L5 level increased the likelihood of FASV 2.56 and 1.81 times, respec-tively. Multivariate logistic regressions analysis determined PSA was a significant factor associated with FASV. Pearson r between PSA and the distance between midline and entry point was 0.905 (P < .0001). Adding one degree of convergence in PSA led to a mean 0.87 lower odds of an FASV event, regardless of surgical techniques. In 90% of patients in the OS and MIS groups, PSA with FASV was < 11.9° and <15.9° at L4 level, and <15.9° and <21.8° at L5 level, respectively.

CONCLUSION

PSAs played an important role in FASV. MIS allowed greater PSAs and resulted in fewer incidences of FASV. To avoid FASV in 90% of patients, the PSAs might be at least 11.9° and 15.9° at L4 level, and 15.9° and 21.8° at L5 level for OS and MIS techniques, respectively.Level of Evidence: 3.